What type of bond forms between two oxygen atoms?
a. nonpolar covalent
b. ionic
c. metallic
d. polar covalent

A double covalent bond.

Explanation:

A double covalent bond forms between two oxygen atoms.

A double covalent bond is when two pairs of electrons are shared between the atom. Usually, there is only one pair, rather than two pairs.

b is the correct

considering the question as per the attachment

here we can see that the radon nuclide has 222 as the atomic mass number and 86 as the atomic number.

when it undergoes nuclear fission it gives polonium which has atomic mass number as 218 and atomic number will be 84 along with a helium nucleus which has 4 atomic mass number and 2 as its atomic number.

222 = 218 + 4 (atomic mass number)

86 = ? + 2; therefore ? = 86-2 = 84.

the atomic mass number of polonium will be 84.